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Anhinga
This bird, dubbed "Water Turkey," can be found swimming in murky swamps, roosting in tall trees, or soaring overhead. The way this bird swims makes it known as the "snake bird." Appearance Anhingas are large and slender waterbirds with long fan-like tails that resemble a turkey's tail. They have a long S-shaped neck and a dagger-like bill, adapted for a rapid thrust to catch fish. In flight, Anhingas look like a flying cross; the wings are held out flat and the neck and tail stick straight out. They have slim bodies and look rather flattened in flight. They are 29.5-37.4 inches (75-95 centimeters) in length, 46.7-47.6 ounces (1325-1350 grams) in weight, and 42.9 inches (109 centimeters) in wingspan. Adult male Anhingas are black with silvery to white streaks on the back and wings. Females and immatures have a pale tan head, neck, and breast. The bill, legs, and feet are yellowish orange. Occurrence Anhingas can be found on the coasts of Central America and south eastern United States. They are short-distance partial migrants. The northernmost individuals move south within the United States or farther south to Mexico for the winter. The Anhinga lives in shallow, slow-moving, sheltered waters and uses nearby perches and banks for drying and sunning. It's rarely found out of freshwater except during severe droughts. Anhingas are generally not found in extensive areas of open water, though it may nest on edges of open bays and lakes. The Anhinga may also breed in saltwater colonies and feed in freshwater. Life History Diet The Anhinga's diet consists of mostly fish. with very small amounts of crustaceans and invertebrates. They feed primarily on "rough" fish of little value to humans. They hunt for fish while swimming underwater or at surface. Not usually fast swimmers, Anhingas mostly wait for fish to come near, then impale them with a lightning-fast thrust of their half-opened bill. They usually stab with both mandibles, but may use the upper mandible only on small fish. Their prey often tossed in air, then swallowed headfirst. Nesting The Anhinga typically nests in loose groups of several to hundreds of pairs, and sometimes with other colonial waterbirds. The nest is usually in a tree near to water or overhanging it. The male begins nest construction before he has a mate, by placing large sticks and green material in the forks of trees. The male collects nearly all the nesting material, and the female then finishes building. The nest is a bulky platform of sticks, somewhat more compact than heron nests. It is then lined with soft plant material. Over time, excrement can build up on the outer rim of the nest giving it a white appearance. Anhingas lay 2-5 eggs in each clutch. They produce only one brood per year. The eggs have a length of 1.9-2.3 inches (4.7-5.8 centimeters) and a width of 1.3-1.5 inches (3.3-3.8 centimeters). Incubation period is 26-30 days and nesting period is 14-21 days. Anhinga eggs are conspicuously pointed at one end, pale bluish green, and overlaid with a chalky coating. Hatchlings are naked, with open eyes. Behavior The Anhinga swims lower in the water than many other birds due to its reduced buoyancy--a result of wetted plumage and dense bones. When at the surface, it tends to swim low in the water, often with only the neck and head above the water, and sometimes with only the bill exposed. The Anhinga is also an adept soarer. While soaring, it holds its wings flat and straight, its neck outstretched or held with a slight kink; its long, straight tail is conspicuous. Anhingas often use thermals for soaring, and may achieve altitudes of several thousand feet. Sounds Calls Anhingas are generally silent expect when they are near the nest. Males and females make a loud clicking sound during nest exchanges that sounds a little like a treadle-operated sewing machine or a croaking frog with a sore throat. Conservation Anhingas are uncommon throughout their range and they reside in areas that can be difficult to reach, thus obtaining a relatively accurate estimate of their population is difficult. According to the North American Breeding Bird Survey, the best estimate of populations state that numbers have increased by nearly 1.5% between 1966 and 2015. Partners in Flight estimates the global breeding population at 83,000 individuals. Based on the population size, distribution, threats, and population trends, the species rates a 9 out of 20 on the Continental Concern Score. It is not on the Partners in Flight Watch List and is a species of low conservation concern. Potential threats to Anhingas include wetland which may reduce available habitat for Anhinga. Discarded fishing lines also pose a threat because the birds can easily get tangled up in them. Gallery Female Anhinga.jpg|Female/immature Anhinga flight.jpg|Female in flight. Anhinga portrait.jpg|Portrait of male. Immature Anhinga.jpg|Immature drying its wings off. Swimming Anhinga.jpg|Female/immature swimming. Anhingas are usually not fast swimmers. Anhingas.jpg|Adult male with juveniles. Trivia * Unlike most waterbirds, the Anhinga doesn't have waterproof feathers. Their wet feathers and dense bones help them slowly submerge their bodies under the water so they can slyly stalk fish. * The name Anhinga comes from the Tupi Indians in Brazil, meaning "devil bird" or "evil spirit of the woods." * The oldest recorded Anhinga was at least 12 years old. * Anhingas are called Anhinga Americana in Spanish and Anhinga d'Amérique in French. Bibliography * See Birds Forever's profile page. Category:Anhingidae Category:Suliformes Category:Aves Category:Birds of North America